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EB2750QFN-AA
FPM2750QFN 1.7 - 2.0GHz LNA EVALUATION BOARD
FEATURES
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Measured @ 1.85GHz
23.5 dBm Output Power
17.5 dB Small Signal Gain
0.60 dB Noise Figure
33 dBm OIP3 measured @ Pout = 5dBm (per tone)
Bias 3V, 50mA
DESCRIPTION AND APPLICATIONS
The data given above is based on measurements taken on the evaluation board described
in this data sheet. This evaluation board is a balanced, dual biased, low noise amplifier. It
is reactively matched at a frequency of 1700 to 2000 MHz. The active device is a
FPM2750QFN; a double-heterojunction, 750 μm gate periphery PHEMT.
Biasing can be applied at the bias pins on the top and bottom of the board. A negative
gate voltage is required for current limiting. Ground connection should be established
prior to the gate and drain bias connections. This board is thin and flexible, so caution
should be exercised when connecting it to coaxial cables.
PERFORMANCE
Freq: (GHz)
N.F.1 (dB)
1.70
0.60
1.75
0.61
1.80
0.60
1.85
0.60
1.90
0.60
1.95
0.60
2.00
0.62
1. Includes input coupler loss of 0.12dB
7628 Thorndike Road, Greensboro, NC 27409-9421 · For sales or technical support,
contact RFMD at (+1) 336-678-5570 or [email protected].
EB2750QFN-AA
FPM2750QFN 1.7 - 2.0GHz LNA EVALUATION BOARD
BOARD LAYOUT AND SCHEMATIC
Vd1
1.0uF
33pF
P4
0.01uF
33pF
L3
Lg
0.01uF
R1
P3
Ld
P1
33pF
L1
33pF
L2
C1
33pF
C2
33pF
A2
f 1SF
xxxx
A1
Ld
Lg
L4
Q1
R2
33pF
33pF
0.01uF
0.01uF
P5
P6
1.0uF
P2
Vd2
The circuit used was designed using Roger 4350 material with a core thickness of 30 mils
and 0.5oz copper cladding. The dielectric constant is 3.48
FPM2750QFN EVAL Board 0.01uF
Schematic
33pF
@ 1.7 - 2.0GHz
-Vg
Vd
0.01uF
33pF
20 Ohm
33pF
1.0uF
22 nH
22 nH
L1
50 Ohm
33pF
C3
RF IN
50 Ohm
L3
33pF
C4
L2
33pF
L4
22 nH
33pF
RF OUT
22 nH
33pF
20 Ohm
0.01uF
1.0uF
0.01uF -Vg
Vd
7628 Thorndike Road, Greensboro, NC 27409-9421 · For sales or technical support,
contact RFMD at (+1) 336-678-5570 or [email protected].